Paint brush and paint roller are well known tool for applying paint over surfaces of building and walls. For painting large surfaces, paint roller and pan remain the instruments of choice for painting professionals and do-it-yourself individuals because they are inexpensive and apply paint consistently. However, the need to replenish the roller frequently attracts a number of new proposals and invention.
In general, the prior art teaches the combination of internal paint reservoirs and either a single or plurality of rollers. See, for example, U.S. Pat. Nos. 3,905,295; 4,167,349; and the list of patents disclosed in U.S. Pat. No. 4,555,195. These prior art painting tools having internal paint reservoirs and roller(s) have a common feature: paint from the reservoirs is applied over the external surface of the roller before the paint is introduced to the target surface.
The absence of these prior art paint tools from the market may be attributed to the fact that these alternatives are expensive, difficulty to maintain, and cumbersome to use. The higher expected cost is related to the large number of auxiliary rollers besides the main roller. Moreover, the complicated structure and movement of painting tool such as U.S. Pat. Nos. 3,905,295 and 4,555,195 suggest that it can be used at most once as coagulated paint clogs the intermediate rollers. Finally, the prior art paint reservoirs are disposed quite a distance off the longitudinal axis of the main rollers. As the reservoir when filled with paint is heavier, the center of gravity of the prior art paint rollers is away from the longitudinal axis of the roller. It follows that the user will find these prior art paint rollers less maneuverable than the regular paint roller.